/*
 * Level.java 22 oct. 2011
 *
 * Sweet Home 3D, Copyright (c) 2011 Emmanuel PUYBARET / eTeks <info@eteks.com>
 *
 * This program is free software; you can redistribute it and/or modify
 * it under the terms of the GNU General Public License as published by
 * the Free Software Foundation; either version 2 of the License, or
 * (at your option) any later version.
 *
 * This program is distributed in the hope that it will be useful,
 * but WITHOUT ANY WARRANTY; without even the implied warranty of
 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
 * GNU General Public License for more details.
 *
 * You should have received a copy of the GNU General Public License
 * along with this program; if not, write to the Free Software
 * Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA  02111-1307  USA
 */
package com.eteks.sweethome3d.model;

import java.beans.PropertyChangeListener;
import java.beans.PropertyChangeSupport;
import java.io.IOException;
import java.io.ObjectInputStream;
import java.io.Serializable;

/**
 * A level in a home.
 * @author Emmanuel Puybaret
 * @since 3.4
 */
public class Level implements Serializable, Cloneable
{
	private static final long serialVersionUID = 1L;
	
	/**
	 * The properties of a level that may change. <code>PropertyChangeListener</code>s added 
	 * to a level will be notified under a property name equal to the string value of one these properties.
	 */
	public enum Property
	{
		NAME, ELEVATION, HEIGHT, FLOOR_THICKNESS, BACKGROUND_IMAGE, VISIBLE, VIEWABLE, ELEVATION_INDEX
	};
	
	private String name;
	private float elevation;
	private float floorThickness;
	private float height;
	private BackgroundImage backgroundImage;
	private boolean visible;
	private boolean viewable;
	private int elevationIndex;
	
	private transient PropertyChangeSupport propertyChangeSupport = new PropertyChangeSupport(this);
	
	/**
	 * Creates a home level from an existing level.
	 * @param name  the name of the level
	 * @param elevation the elevation of the bottom of the level
	 * @param floorThickness the floor thickness of the level
	 * @param height the height of the level 
	 */
	public Level(String name, float elevation, float floorThickness, float height)
	{
		this.name = name;
		this.elevation = elevation;
		this.floorThickness = floorThickness;
		this.height = height;
		this.visible = true;
		this.viewable = true;
		this.elevationIndex = -1;
	}
	
	/**
	 * Initializes new level fields to their default values 
	 * and reads level from <code>in</code> stream with default reading method.
	 */
	private void readObject(ObjectInputStream in) throws IOException, ClassNotFoundException
	{
		this.propertyChangeSupport = new PropertyChangeSupport(this);
		this.visible = true;
		this.viewable = true;
		this.elevationIndex = -1;
		in.defaultReadObject();
	}
	
	/**
	 * Adds the property change <code>listener</code> in parameter to this level.
	 */
	public void addPropertyChangeListener(PropertyChangeListener listener)
	{
		this.propertyChangeSupport.addPropertyChangeListener(listener);
	}
	
	/**
	 * Removes the property change <code>listener</code> in parameter from this level.
	 */
	public void removePropertyChangeListener(PropertyChangeListener listener)
	{
		this.propertyChangeSupport.removePropertyChangeListener(listener);
	}
	
	/**
	 * Returns the name of this level.
	 */
	public String getName()
	{
		return this.name;
	}
	
	/**
	 * Sets the name of this level. Once this level 
	 * is updated, listeners added to this level will receive a change notification.
	 */
	public void setName(String name)
	{
		if (name != this.name && (name == null || !name.equals(this.name)))
		{
			String oldName = this.name;
			this.name = name;
			this.propertyChangeSupport.firePropertyChange(Property.NAME.name(), oldName, name);
		}
	}
	
	/**
	 * Returns the elevation of the bottom of this level. 
	 */
	public float getElevation()
	{
		return this.elevation;
	}
	
	/**
	 * Sets the elevation of this level. Once this level is updated, 
	 * listeners added to this level will receive a change notification.
	 */
	public void setElevation(float elevation)
	{
		if (elevation != this.elevation)
		{
			float oldElevation = this.elevation;
			this.elevation = elevation;
			this.propertyChangeSupport.firePropertyChange(Property.ELEVATION.name(), oldElevation, elevation);
		}
	}
	
	/**
	 * Returns the floor thickness of this level. 
	 */
	public float getFloorThickness()
	{
		return this.floorThickness;
	}
	
	/**
	 * Sets the floor thickness of this level. Once this level is updated, 
	 * listeners added to this level will receive a change notification.
	 */
	public void setFloorThickness(float floorThickness)
	{
		if (floorThickness != this.floorThickness)
		{
			float oldFloorThickness = this.floorThickness;
			this.floorThickness = floorThickness;
			this.propertyChangeSupport.firePropertyChange(Property.FLOOR_THICKNESS.name(), oldFloorThickness,
					floorThickness);
		}
	}
	
	/**
	 * Returns the height of this level.
	 */
	public float getHeight()
	{
		return this.height;
	}
	
	/**
	 * Sets the height of this level. Once this level is updated, 
	 * listeners added to this level will receive a change notification.
	 */
	public void setHeight(float height)
	{
		if (height != this.height)
		{
			float oldHeight = this.height;
			this.height = height;
			this.propertyChangeSupport.firePropertyChange(Property.HEIGHT.name(), oldHeight, height);
		}
	}
	
	/**
	 * Returns the plan background image of this level.
	 */
	public BackgroundImage getBackgroundImage()
	{
		return this.backgroundImage;
	}
	
	/**
	 * Sets the plan background image of this level and fires a <code>PropertyChangeEvent</code>.
	 */
	public void setBackgroundImage(BackgroundImage backgroundImage)
	{
		if (backgroundImage != this.backgroundImage)
		{
			BackgroundImage oldBackgroundImage = this.backgroundImage;
			this.backgroundImage = backgroundImage;
			this.propertyChangeSupport.firePropertyChange(Property.BACKGROUND_IMAGE.name(), oldBackgroundImage,
					backgroundImage);
		}
	}
	
	/**
	 * Returns <code>true</code> if this level is visible.
	 */
	public boolean isVisible()
	{
		return this.visible;
	}
	
	/**
	 * Sets whether this level is visible or not. Once this level is updated, 
	 * listeners added to this level will receive a change notification.
	 */
	public void setVisible(boolean visible)
	{
		if (visible != this.visible)
		{
			this.visible = visible;
			this.propertyChangeSupport.firePropertyChange(Property.VISIBLE.name(), !visible, visible);
		}
	}
	
	/**
	 * Returns <code>true</code> if this level is viewable.
	 * @since 5.0
	 */
	public boolean isViewable()
	{
		return this.viewable;
	}
	
	/**
	 * Sets whether this level is viewable or not. Once this level is updated, 
	 * listeners added to this level will receive a change notification.
	 * @since 5.0
	 */
	public void setViewable(boolean viewable)
	{
		if (viewable != this.viewable)
		{
			this.viewable = viewable;
			this.propertyChangeSupport.firePropertyChange(Property.VIEWABLE.name(), !viewable, viewable);
		}
	}
	
	/**
	 * Returns <code>true</code> if this level is viewable and visible.
	 * @since 5.0
	 */
	public boolean isViewableAndVisible()
	{
		return this.viewable && this.visible;
	}
	
	/**
	 * Returns the index of this level used to order levels at the same elevation.
	 * @since 5.0
	 */
	public int getElevationIndex()
	{
		return this.elevationIndex;
	}
	
	/**
	 * Sets the index of this level used to order levels at the same elevation.
	 * @since 5.0
	 */
	public void setElevationIndex(int elevationIndex)
	{
		if (elevationIndex != this.elevationIndex)
		{
			int oldElevationIndex = this.elevationIndex;
			this.elevationIndex = elevationIndex;
			this.propertyChangeSupport.firePropertyChange(Property.ELEVATION_INDEX.name(), oldElevationIndex,
					elevationIndex);
		}
	}
	
	/**
	 * Returns a clone of this level.
	 */
	@Override
	public Level clone()
	{
		try
		{
			Level clone = (Level) super.clone();
			clone.propertyChangeSupport = new PropertyChangeSupport(clone);
			return clone;
		}
		catch (CloneNotSupportedException ex)
		{
			throw new IllegalStateException("Super class isn't cloneable");
		}
	}
}
